1. Field of the Invention
The present invention relates to a gas sensor for determining gas components in gas mixtures, e.g., in the exhaust gas of internal combustion engines.
2. Description of Related Art
Field-effect transistors are used, among other things, in determining gas components in gas mixtures. For example, a gate electrode of the field-effect transistor reacts sensitively to gas components to be determined, thereby triggering a change in a control voltage applied to the gate electrode. The occurring change in the current flow resulting between the source electrode and the drain electrode is detected and associated with the concentration of a gas component.
If gas components are determined in exhaust gases of internal combustion engines, the determination of individual gas components is impaired by cross sensitivities to other gas components. In order to largely prevent this impairment of the measuring signals by interfering gas components, it is known from published German patent document DE 10 2004 019 641 A1, for example, to provide an FET-based gas sensor with a gas channel for diffusing a measuring gas to a gas-sensitive layer, an electrochemical element being introduced into the gas channel which is used for converting interfering gases.